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  1. #1
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    AC switch with DC control

    Dear sirs,

    I have a PLC with 12 x 127Vac inputs and need to be drived by 24V sensors. My first try was using relays but the sensors are very fast and run at +-10Hz so the stress of the relays will destroy then in a very short time. Was thinking to use one MOC3010 for each channel. According to the manufacturer of the PLC each input looks like the attached schematic. My idea is attached too.

    Any idea will be very usefull.

    Regards,

    Fernando

    •   Alt7th December 2017, 17:29

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  2. #2
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    Re: AC switch with DC control

    Hi,

    The PLC input current will be low.
    But according datasheet the MOCs are not made for directely drive some load.
    In your case a small SCR at the MOC output will rectify this.

    Did you consider to use an SSR or a photomos relay? like LH1546ADF

    Klaus
    Please don´t contact me via PM, because there is no time to response to them. Thank you.



    •   Alt7th December 2017, 18:16

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  3. #3
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    Re: AC switch with DC control

    Tocayo;
    it is best if you employ a solid state relay (SSR), which takes care of the details of driving a Triac from a logic line.
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